Mucosal-associated invariant T (MAIT) cells are innate T cells that were first believed to specialize in anti-bacterial responses, however, have shown to be involved in other immune responses, for example, against viruses, as well as processes of tissue-repair.

After a lung infection with bacteria containing riboflavin metabolic pathways, Mucosal-associated invariant T (MAIT) cells expand and remained expanded in the tissue for long-term. Subpopulations of KLRG1+ and CD127+ MAIT cells are observable after infection, but only CD127+ population is detectable at steady state. Some of the transcriptional changes observable long-term after exposure are also found in canonical T cell memory populations when compared to naïve cells. We plan to use these conventional immunological memory overlapping genes and MAIT-exclusive gene hits to perform a in vivo CRISPR screen that would help us determine which genes enable the generation of these long-term expanded MAIT cells.